The field of the present invention relates to pedestals for video, television, and motion picture cameras.
Video, television, and motion picture cameras must often be positioned in a particular way for a video or film sequence. The camera must also often move or sweep in azimuth or elevation, and the entire camera may need to be translated or moved over the ground surface, e.g., to follow an action sequence or obtain a desired cinematographic effect.
Generally, all movement of the camera must be uniform and smooth without any bumping, rocking, tilting, vibration or other movement that will cause the recorded images to jump when viewed on a screen. Mobile camera pedestals are commonly used to obtain such a wide range of movement. Typically, camera pedestals have a triangular base with a wheel or wheel pair at each of the three comers of the base. Some camera pedestals, for example as described in U.S. Pat. Nos. 5,820,088; 5,318,313; 5,410,684; and 5,516,070 incorporated herein by reference, have a rectangular base with 4 wheels or wheel pairs and allow the camera to be raised, lowered, turned, swept (in azimuth), tilted, or elevated.
Ideally, the camera pedestal should support and move the camera with an absolute minimum of noise, vibration, rocking, tilting, jarring, etc. However, reaching these objectives can present difficult engineering challenges. For many of the camera pedestal""s functions, even precision machining can not completely eliminate vibrations caused by internal mechanisms. Additional vibrations are also frequently caused by the camera pedestal moving over an uneven surface. To reduce or eliminate the unwanted effects vibrations cause to the recorded images, cameras are often mounted on the pedestal using a separate vibration dampening device.
The goal of obtaining the smoothest image possible, however, is not completely met by isolating the camera from vibrations. The same vibrations that effect the operation of the camera can also effect the person operating the pedestal, e.g., a camera operator or videographer, cinematographer, dolly grip, etc. Smooth changes in camera position during a filming sequence are dependent upon the pedestal operator""s skills and steady hands. The pedestal operator uses the different mechanisms provided by the camera pedestal to change camera positions. For example, in translating or moving the camera pedestal over the ground, the pedestal operator pushes and steers the camera pedestal using a steering ring which is typically mounted just below the camera at the top of the pedestal.
In current camera pedestal designs, such as in U.S. Pat. No. 5,820,088, the steering ring is rigidly attached to the camera pedestal. Through this rigid connection, vibrations from the entire camera pedestal are easily transmitted through the steering ring and into the hands of the pedestal operator as the camera is guided through its movements. The rigidly attached steering ring can have the effect of actually amplifying vibrations from the camera pedestal. In addition, any vibrations or impact on the ring can be transmitted through the pedestal to the camera.
Accordingly, it is an object of the invention to provide an improved steering ring for a camera pedestal which reduces shock and vibrations.
In a first aspect of the invention, a steering ring for a camera pedestal is mechanically isolated from the body of the camera pedestal. Preferably, the steering ring is supported on the pedestal via vibration absorbing or blocking materials, such as elastomers. Vibration and shock to and from the steering ring is reduced. This improves the feel of the steering ring in the pedestal operator""s hands, and also tends to reduce vibration transmitted from the steering ring to the camera lens.
In a second aspect of the invention, the steering ring is attached to the pedestal body via spring elements. The spring elements preferably allow for vertical flexing of the steering ring, reducing vibration to and from the steering ring.